If you're looking for manga similar to Youkai Watch: Wakuwaku Nyanderful Days, you might like these titles.
Arata Miyako isa new government worker assigned to the Shinjuku Ward Office's "Nighttime Regional Relations" department. Each of Tokyo's 23 wards has one such department, which were established to solve paranormal and occult-related events. Arata can understand non-human speech that no one else understands, and he encounters a youkai (supernatural entity) at Shinjuku Gyoen park that calls him Abe no Seimei — the name of a historical Japanese occultist and diviner.
Where else would a girl with the power to translate any tome she sets in her lap reside except a library? Sure, some books may be more dangerous than others, but that's far from discouragement for a true bibliophile like Kosuzu Motoori!
This is the visual diary of Kiitarou's experience with youkai. He's a boy with a very strong spirit sense, but when he entered a forbidden storehouse, he was kicked out of his home. He soon found a new place to live, where he met a house spirit named Suzu. He and Suzu soon began to attract all kinds of spirit creatures, starting with a nurikabe and mokumokuren. What kind of folkloric creature will he meet next?